From 522ac5232ad7b9cd644ebbd9d7ec476e0c148284 Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Fri, 7 Sep 2018 14:16:24 +0800 Subject: btrfs: Ensure btrfs_trim_fs can trim the whole filesystem commit 6ba9fc8e628becf0e3ec94083450d089b0dec5f5 upstream. [BUG] fstrim on some btrfs only trims the unallocated space, not trimming any space in existing block groups. [CAUSE] Before fstrim_range passed to btrfs_trim_fs(), it gets truncated to range [0, super->total_bytes). So later btrfs_trim_fs() will only be able to trim block groups in range [0, super->total_bytes). While for btrfs, any bytenr aligned to sectorsize is valid, since btrfs uses its logical address space, there is nothing limiting the location where we put block groups. For filesystem with frequent balance, it's quite easy to relocate all block groups and bytenr of block groups will start beyond super->total_bytes. In that case, btrfs will not trim existing block groups. [FIX] Just remove the truncation in btrfs_ioctl_fitrim(), so btrfs_trim_fs() can get the unmodified range, which is normally set to [0, U64_MAX]. Reported-by: Chris Murphy Fixes: f4c697e6406d ("btrfs: return EINVAL if start > total_bytes in fitrim ioctl") CC: # v4.4+ Signed-off-by: Qu Wenruo Reviewed-by: Nikolay Borisov Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman --- fs/btrfs/extent-tree.c | 10 +--------- fs/btrfs/ioctl.c | 11 +++++++---- 2 files changed, 8 insertions(+), 13 deletions(-) (limited to 'fs') diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 80cd28456f08..13ff0fdae03e 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -10708,17 +10708,9 @@ int btrfs_trim_fs(struct btrfs_root *root, struct fstrim_range *range) u64 start; u64 end; u64 trimmed = 0; - u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy); int ret = 0; - /* - * try to trim all FS space, our block group may start from non-zero. - */ - if (range->len == total_bytes) - cache = btrfs_lookup_first_block_group(fs_info, range->start); - else - cache = btrfs_lookup_block_group(fs_info, range->start); - + cache = btrfs_lookup_first_block_group(fs_info, range->start); while (cache) { if (cache->key.objectid >= (range->start + range->len)) { btrfs_put_block_group(cache); diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 150d3c891815..3379490ce54d 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -378,7 +378,6 @@ static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg) struct fstrim_range range; u64 minlen = ULLONG_MAX; u64 num_devices = 0; - u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy); int ret; if (!capable(CAP_SYS_ADMIN)) @@ -402,11 +401,15 @@ static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg) return -EOPNOTSUPP; if (copy_from_user(&range, arg, sizeof(range))) return -EFAULT; - if (range.start > total_bytes || - range.len < fs_info->sb->s_blocksize) + + /* + * NOTE: Don't truncate the range using super->total_bytes. Bytenr of + * block group is in the logical address space, which can be any + * sectorsize aligned bytenr in the range [0, U64_MAX]. + */ + if (range.len < fs_info->sb->s_blocksize) return -EINVAL; - range.len = min(range.len, total_bytes - range.start); range.minlen = max(range.minlen, minlen); ret = btrfs_trim_fs(fs_info->tree_root, &range); if (ret < 0) -- cgit v1.2.3